Saturday, 28 February 2015

Understanding the concept of ISO

By definition ISO is a measure of the camera sensor sensitivity to light. The higher the ISO setting, the more sensitive we terhada sensor light.

To get a clear picture of the ISO setting on the camera we (ASA in the case of photographic film), think about a bee community.

And if my camera set at ISO 200 means I have 200 worker bees.

An ISO is a worker bee. If I set the camera at ISO 100, it means I have 100 worker bees.

The task of each worker bees are picked light entering through the lens of the camera and make pictures. If we use the lens aperture identical and equally we set at f / 3.5, but I set the ISO at 200 while your 100 (think again about the worker bees), then the image has to be faster who completed?

Outline:

When we add the ISO settings from 100 to 200 (the aperture that is always constant - we lock the aperture at f / 3.5 or through Aperture Priority mode - A or Av), we shorten the time needed to manufacture a photo on our camera sensor by half ( 2 times faster), a shutter speed of 1/125 to 1/250 sec.

You can try this sense in the case of the aperture, try to set the shutter speed at 1/125 we always constant (or through Shutter Priority modes - S or Tv), and change-change your ISO settings in multiples of 2; eg from 100 to 200 to 400 ... and so on, look at the changes in the amount of your aperture

When we add more ISO to 400, we cut the time of making photo by half again: 1/500 sec.

Whenever exposure shorten as much as half, we call raise sxposure by 1 stop.